Camera cranes are used to position and maneuver motion picture or video cameras. Camera cranes typically have a crane arm mounted onto a mobile base or vehicle, with a camera platform at one end of the crane arm, and counterweights at the other end of the arm. The crane arm can be pivoted or tilted up or down, and panned from side to side, to obtain a desired camera position, while the mobile base remains stationary. Some camera crane arms can also extend telescopically. These movements allow a camera on a platform at the front end of the arm to move into a wide range of positions. To follow a moving subject during filming, or to move the camera around a subject, or move diagonally in any direction, the motion base is pushed and steered by a film crew. The motion base may also be moved on tracks, if the ground or floor is too irregular for smooth filming.
As filming often takes place outside of a studio (on location), the mobile base is advantageously portable, so that, if necessary, it can be carried to the filming location by the film crew. Accordingly, the mobile base is advantageously light weight and compact. On the other hand, the mobile base should be able to provide a steady platform for supporting and moving a camera crane arm. To reduce the rolling friction and noise resulting from tire scrubbing when steered on a curved path, mobile bases often have steering transmissions intended to provide geometrically corrected steering. While various mobile camera crane bases have successfully been used in the past, there remains a need for an improved mobile camera crane base which can be easily transported, provides advantageous steering characteristics, is quickly adaptable for both ground and track use, and which provides a stable vehicle for a camera crane arm.